Mixed-mode I and II fatigue crack growth retardation due to overload: An experimental study

Mixed-mode fatigue crack propagation simulation by means of Geq and walker models of the structural steel S355

“…To determine the value of the coefficient β, the Mean Relative Error (MRE) between the numerical simulation results using the median material coefficient of the Walker equation and the experimental data was calculated according to Eqn. (7). Since the test is conducted at three loading angles, three MRE values can be calculated for a value of β, and the maximum, minimum and mean values of the three MRE are given in Fig.…”

“…The fatigue life of the mixed-mode I + III fatigue specimens decreased with the increase of the ratio of torsional torque to bending torque. Rege et al [7] studied the phenomenon of fatigue crack propagation retardation due to overload and concluded that overload will lead to the delay of fatigue crack propagation under mixed loading. Pedrosa et al [8] proposed a unified two-stage fatigue methodology to assess the fatigue crack propagation of S355 steel considering the plasticity induced crack closure effect.…”

Using the linear damage summation hypothesis in determining the endurance limit of titanium alloy

“…With an insufficient amount of fatigue tests, the parameters of Equation ( 1) are determined on the basis of regression analysis, the equation of the averaged fatigue curve corresponding to the fracture probability P = 0.5 is established. With a sufficient amount of testing, a family of curves can be constructed for a number of fixed levels of fracture probabilities (Kunitskii et al, 1988(Kunitskii et al, , 1990Panfilov et al, 2020;Rege et al, 2019). For the experiments, an alloy of technical titanium was used, intended for the manufacture of products with high strength with sufficient plasticity and toughness, high resistance and small plastic deformations, brittle and fatigue fracture.…”

Fatigue crack growth of butt welded joints subjected to mixed mode loading and overloading

“…The problem becomes more complicated if mixed mode conditions prevail at the crack tip by changing in the overload direction due to a special event such as thermo-shock or an operating error or temporary change in the loading direction [11]. For this purpose, some studies have focused on the fatigue crack growth behavior of materials subjected to mixed mode overload [17][18][19][20][21][22][23][24]. Sander and Richard [17] numerically showed that an increase in mode II portion of the overload causes a decrease in crack closure.…”

“…By applying mixed mode overload to tubular specimens, Rege et al [23] showed that retardation length is more than two times longer than the size of the overload plastic zone obtained from a linear elastic solution. Shahani et .al [24] proposed two models to evaluate retardation of fatigue crack growth of non-welded specimen under mixed mode overload by extending the Wheeler retardation model.…”